1. Field of the Invention
The present invention relates to a cassette for a tape printer.
2. Background Art
Known tape printing apparatus of the type with which the present invention is generally concerned are disclosed in published European Patent Applications EP-A-0 322 918 and EP-A-0 322 919 (Brother KK) and EP-A-0 267 890 (Varitronic). The printers each include a printing device having a cassette receiving bay for receiving a cassette or tape holding case. In EP-A-0 322 918, the tape holding case houses an ink ribbon, a transparent image receiving tape and a double-sided adhesive tape which is secured at one of its adhesive coated sides to the image tape after printing and which has a backing paper peelable from its other adhesive side. With both these apparatus, the image transfer medium (ink ribbon) and an image receiving tape (substrate) are in the same cassette.
The present invention was developed as a different type of tape printing apparatus which is described for example in U.S. Pat. No. 5,456,545. In this printing apparatus, the substrate tape is similar to that described in EP-A-0 267 890 (ie. comprises an image receiving layer and a releasable backing layer) but is housed in its own tape holding case while the image transfer ink ribbon is similarly housed in its own tape holding case.
In all of these cases, the image receiving tape passes in an overlap manner with the ink ribbon to a print zone consisting of a fixed print head and a platen against which the print head can be pressed to cause an image to transfer from the ink ribbon to the image receiving tape. There are many ways of doing this, including dry lettering or dry film impression, but the most usual way at present is by thermal printing where the print head is heated and the heat causes ink from the ink ribbon to be transferred to the ink receiving tape. Alternatively, the print head may be in direct contact with a thermally sensitive image receiving tape whereby when the print head is heated, an image is defined on the image receiving tape.
A disadvantage of the known tape cassettes is that once the supply of tape housed in the cassette is printed, the user needs to buy an entirely new cassette, while the empty cassette is discarded. In order to avoid wastage of material, it has thus been proposed to have refillable cassettes, into which the user can insert new printing tape and/or ink ribbon. Such cassettes are described eg. in European Patent Applications EP-A-0 625 427, EP-A-0 629 509, EP-A-0 630 756, EP-A-0 633 141, EP-A-0 635 375, EP-A-0 694 415, EP-A-0 704 311, EP-A-0 734 878, EP-A-0 790 134, and German Patent DE-U-295 20 421.
Such cassettes allow the user to use one tape cassette with a multiplicity of image receiving tapes and/or image transfer tapes (ink ribbon). A disadvantage is however that the refillable cassettes known in the prior art only allow inserting certain width of tape. Thus, a user needs a relatively high number of tape cassettes, since this number equals the number of different tape width which are intended to be used.